2014-02-26

Mac OS X Lion: Scan for wireless networks

Mac OS X Lion provides a command line tool to scan for wireless networks and print useful information about the networks:

/System/Library/PrivateFrameworks/Apple80211.framework/Versions/A/Resources/airport -s

Also, to see additional information about the currently active wireless connection hold down the Option key while clicking on the Airport Symbol in the menu bar.


2014-02-17

Common bashrc settings

There are my personal preferences. Your preferences may differ.

alias e=jed
alias mv="mv -i"
alias cp="cp -i"
alias rm="rm -i"
complete -r
export LANG=C
export EDITOR=jed
export PATH=$PATH:${HOME}/bin

2014-02-07

Zotac Zbox ID18 Linux Server


  • Zotac Zbox ID18
  • Samsung SSD 840 EVO 1TB
  • 4GB RAM (SODIMM 1600)
  • Ubuntu 13.10
Samsung SSD firmware update: The process is quite broken:

  • download the 'Windows' Firmware update for the 840 EVO
  • mount it
  • dd the btdsk.img onto a USB stick
  • put the USB stick into the Zotac
  • change the Zotac BIOS so it boots from the USB stick
  • reboot
  • ignore all error messages about missing partitions
  • eventually the Samsung Firmware Update program comes up
  • take note of the Firmware revision
  • follow the instructions of the program
  • wait
  • ignore the message about power cycling the SSD, since you cannot power cycle it in isolation
  • ignore the message about the firmware update being unsuccessful
  • reboot (still from the USB stick)
  • check that you have the new firmware revision
  • Linux shows: ata1.00: ATA-9: Samsung SSD 840 EVO 1TB, EXT0BB6Q, max UDMA/133)
The installation of Ubuntu is quite straight forward.
Recommended settings after installation:
  • Enable TRIM support and avoid unnecessary writes when reading files and dirs:
    • /etc/fstab:
    • UUID= /   ext4    discard,noatime,errors=remount-ro 0       1
  • Reduce amount of disk space reserved for root from 45GB to 1GB:
    • sudo tune2fs /dev/sda1 -m 0.1
  • Install sshd:
    • sudo apt-get install openssh-server
  • Install 'sensors' to check the CPU temp:
    • sudo apt-get install lm-sensors
    • sudo sensors-detect
    • sudo service kmod start
    • sensors
  • Install 'smartmontools' to see the SSD temp and other interesting data:
    • sudo apt-get install smartmontools
    • sudo smartctl -x /dev/sda | grep -i 'Current Temp'
  • Do not start GUI/X
    • edit /etc/default/grub:
      • #GRUB_HIDDEN_TIMEOUT=0
      • GRUB_TIMEOUT=1
      • GRUB_CMDLINE_LINUX_DEFAULT="text"
    • sudo jed /etc/default/grub
    • sudo update-grub
  • I like to install:
    • sudo apt-get install jed apcalc screen minidlna openssh-server samba emacs ispell subversion g++ imagemagick
  • If you have a couple of minutes:
    • sudo apt-get update
    • sudo apt-get upgrade
  • If you would like to manually TRIM the SSD:
    • sudo fstrim -v /
  • Install SAMBA:
Example /etc/samba/smb.conf:
[zotti]
    comment = Share on the Zotac
    path = /zotti
    browsable = yes
    guest ok = yes
    read only = no
    create mask = 0777
    veto files = /.*.pdf/.*.jpg/.DS_Store/._.DS_Store/.*.ini/.*.txt/.*.mov/.*.avi/.*.mpg/.*.png/
    delete veto files = yes
    hide dot files = yes
    hide unreadable = yes


2014-02-03

jed settings for indent=4, just spaces, line numbers on, sane brace insertion

My favorite jed setting in $HOME/.jedrc
USE_TABS = 0;
LINENUMBERS = 2;
% For the following to work you _must_ comment out any c_set_style() call!
C_INDENT = 4;
C_BRACE = 0;
C_BRA_NEWLINE = 0;
C_Colon_Offset = 0;
C_CONTINUED_OFFSET = 4;
public variable C_Class_Offset = 4;